1. Field of the Invention
The present invention relates to a semiconductor device comprising a semiconductor chip such as an IC chip.
2. Description of Related Art
Examples of a semiconductor device package structure include an FCBGA (Flip Chip Ball Grid Array) package structure. FIG. 2 shows an example of the arrangement of a semiconductor device having this FCBGA package structure.
More specifically, a semiconductor device of the FCBGA package type comprises a semiconductor chip 91, a wiring substrate 92 bonded thereto, a stiffener 93 so disposed as to surround the semiconductor chip 91 on the wiring substrate 92, and a heat radiating plate 94 laminated on the semiconductor chip 91 and the stiffener 93.
The semiconductor chip 91 is electrically and mechanically bonded to the surface 92a of the wiring substrate 92 through a plurality of bumps 95 formed on the active surface of the semiconductor chip 91. A plurality of soldering balls 96 serving as external connection terminals are disposed on the reverse face 92b of the wiring substrate 92 which is opposite to the surface 92a bonded to the semiconductor chip 91.
The stiffener 93 is a reinforcing member for keeping the flatness of the wiring substrate 92 and generally made of a metallic material. Accordingly, in manufacturing the semiconductor device having the arrangement above-mentioned, there should be executed steps, i.e., a step of gluing, through an adhesive layer 97, the stiffener 93 onto the surface of the wiring substrate 92 bonded to the semiconductor chip 91, and a step of gluing, through an adhesive layer 98, the stiffener 93 to the heat radiating plate 94. This complicates the manufacturing process, disadvantageously lowering the productivity.
It is an object of the present invention to provide a semiconductor device to be manufactured in a simple process.
According to the present invention, a semiconductor device comprises: a wiring substrate having a wiring pattern; a semiconductor chip disposed on the wiring substrate and electrically connected to the wiring pattern; a heat radiating plate disposed at the side of the semiconductor chip which is opposite to the side thereof facing the wiring substrate, this heat radiating plate being arranged for radiating the heat generated from the semiconductor chip; and a highly elastic member of a synthetic resin so disposed as to surround the semiconductor chip between the wiring substrate and the heat radiating plate.
According to the arrangement above-mentioned, the semiconductor chip is held by and between the wiring substrate and the metallic heat radiating plate, and the highly elastic member is disposed around the semiconductor chip. Accordingly, even though the thickness of the wiring substrate is small (e.g., not greater than 200 xcexcm), the highly elastic member around the semiconductor chip can keep the flatness of the wiring substrate.
Further, the highly elastic member is made of a synthetic resin. Accordingly, the highly elastic member can be formed in a unitary structure with the wiring substrate in any of the following manners. For example, a wiring substrate bonded to a semiconductor chip is set to a mold, a liquefied synthetic resin material is then poured into the mold, and this synthetic resin material is then hardened. Alternatively, a plurality of wiring substrates bonded to semiconductor chips are arranged, a liquefied thermosetting resin material is then applied to the surrounding spaces around the semiconductor chips on the surface of the wiring substrates, and this thermosetting resin material is then hardened. Accordingly, as compared with a semiconductor device made by applying adhesives to a metallic stiffener and bonding the same to the wiring substrate, the semiconductor device of the present invention can be simplified in production process, resulting in improved productivity.
These and other features, objects, advantages and effects of the present invention will be more fully apparent from the following detailed description set forth below when taken in conjunction with the accompanying drawings.